Once you've created an account, you just need to log in to the the app on your mobile device. Simply creating the account will not give you full access unless you log in from within the app. You can see instructions here.
If you've forgotten your password, you can reset your password through the log in screen within the app. Click the menu on the top left and select "Login." Then click the link at the bottom that says "Forgot Password." You will be prompted to enter the same email address you used to sign up for the account and then you will receive a link to reset your password.
If you do not see the "Forgot Password" link, be sure you have updated to the latest version of the app.